中文摘要：

螺旋桨推进轴系中水润滑轴承-轴颈摩擦诱导异常振动、噪声是制约舰艇隐身性能的重要因素,研究其成因机制和影响规律对于识别和有效控制异常振动、噪声具有重要价值。为此,从非线性摩擦和轴系整体动力学耦合的角度对螺旋桨推进轴系摩擦诱导振动问题进行分析。采用速度依赖型的Stribeck摩擦模型描述轴承-轴颈的动摩擦特性,考虑非线性摩擦-扭转振动-横向振动的耦合作用,在此基础上利用Hamilton原理和有限元法建立连续轴系的非线性动力学方程。运用Newmark-β法和Newton-Raphson迭代相结合的方式求解并获取系统非线性动力学响应,分析动摩擦特性及弯-扭耦合作用对轴系摩擦诱导振动的影响规律。结果表明,相较于纯扭转系统,弯-扭耦合系统更容易产生摩擦自激振动。除轴承-轴颈摩擦特性外,不稳定的弯曲模态同样为耦合系统摩擦自激振动的重要成因。

英文摘要：

Unacceptable vibrations and noise induced by the water-lubricated bearing-shaft friction in propeller-shaft systems seriously affect the stealth performance of warships. To find out the basic excitation mechanism has important significance to the recognition and efficient control of the unwanted vibrations and noise. Friction-induced vibration in the propeller-shaft system is studied on the basis of the interactions between the nonlinear friction and the overall system dynamics. A nonlinear mathematical model by using the Hamilton＇s principle in conjunction with the finite element method is formulated. The model accounts for the lateral-torsional vibrations interactions as well as the bearing-shaft friction represented by the Stribeck curve. A numerical method, which combines the Newmark-fl method and the Newton-Raphson iterations, is used to obtain the system dynamic responses. Effects of the frictional characteristics and lateral-torsional interaction on the generation of the friction-induced vibration are analyzed. The results show that the coupling system is more prone to the onset of the instability compared with the pure torsional system. Besides the frictional characteristics, the instability of particular lateral modes is an important factor with regard to the occurrence of the friction-induced self-excited vibration.